Clean conflicting class files from Temporary ASP.NET Files

Class file Conflicts in C:WINDOWSMicrosoft.NETFrameworkv2.0.50727Temporary ASP.NET Files is preventing me from building the solution. Even though I try emptying out the folder, each time Visual Studio starts the build process, it brings in the class file in to the temp folder with the same folder name. If I restart the machine or leave it overnight, project build without error. Is there anyway to tell Visual studio to delete/ignore/clean any lingering class files that could be in the temp folder?

What does aspnet_regiis.exe do

What does aspnet_regiis.exe do exactly other than updating the document mappings to correct aspnet_isapi.dll version, is updating the ASP.NET version from inetmgr same as running aspnet_regiis, I could not find any blog post or article describing the steps this particular batch command does. Please give any links you know of detailing the steps of aspnet_regiis.exe